-Set key used with all modes. Must be set for all modes except @code{print}.

+@item me

+The algorithm to be used for motion estimation. Following values are accepted:

+@table @samp

+@item esa

+Exhaustive search algorithm.

+@item tss

+Three step search algorithm.

+@item tdls

+Two dimensional logarithmic search algorithm.

+@item ntss

+New three step search algorithm.

+@item fss

+Four step search algorithm.

+@item ds

+Diamond search algorithm.

+@item hexbs

+Hexagon-based search algorithm.

+@item epzs

+Enhanced predictive zonal search algorithm.

+@item umh

+Uneven multi-hexagon search algorithm.

+@end table

+Default algorithm is @samp{epzs}.

+

+@item mb_size

+Macroblock size. Default @code{16}.

+

+@item search_param

+Motion estimation search parameter. Default @code{32}.

+

+@item vsbmc

+Enable variable-size block motion compensation. Motion estimation is applied with smaller block sizes at object boundaries in order to make the them less blur. Default is @code{0} (disabled).

+@end table

+@end table

+

+@item scd

+Scene change detection method. Scene change leads motion vectors to be in random direction. Scene change detection replace interpolated frames by duplicate ones. May not be needed for other modes. Following values are accepted:

+@table @samp

+@item none

+Disable scene change detection.

+@item fdiff

+Frame difference. Corresponding pixel values are compared and if it satisfies @var{scd_threshold} scene change is detected.

+@end table

+Default method is @samp{fdiff}.

-@item value

-Set metadata value which will be used. This option is mandatory for

-@code{modify} and @code{add} mode.

+@item scd_threshold

+Scene change detection threshold. Default is @code{5.0}.

+@end table

-@item function

-Which function to use when comparing metadata value and @code{value}.

+@section mpdecimate

-Can be one of following:

-

-@table @samp

-@item same_str

-Values are interpreted as strings, returns true if metadata value is same as @code{value}.

-

-@item starts_with

-Values are interpreted as strings, returns true if metadata value starts with

-the @code{value} option string.

-

-@item less

-Values are interpreted as floats, returns true if metadata value is less than @code{value}.

-

-@item equal

-Values are interpreted as floats, returns true if @code{value} is equal with metadata value.

-

-@item greater

-Values are interpreted as floats, returns true if metadata value is greater than @code{value}.

-

-@item expr

-Values are interpreted as floats, returns true if expression from option @code{expr}

-evaluates to true.

-@end table

-

-@item expr

-Set expression which is used when @code{function} is set to @code{expr}.

-The expression is evaluated through the eval API and can contain the following

-constants:

-

-@table @option

-@item VALUE1

-Float representation of @code{value} from metadata key.

-

-@item VALUE2

-Float representation of @code{value} as supplied by user in @code{value} option.

-@end table

-

-@item file

-If specified in @code{print} mode, output is written to the named file. When

-filename equals "-" data is written to standard output.

-If @code{file} option is not set, output is written to the log with AV_LOG_INFO

-loglevel.

-@end table

-

-@subsection Examples

-

-@itemize

-@item

-Print all metadata values for frames with key @code{lavfi.singnalstats.YDIF} with values